Tapping rod with lime coating



Oct. 16, 1962 c. G. CHAMBERS 3,058,735

TAPPING ROD WITH LIME COATING Filed Jan. 28, 1960 Caswe/l 6. Chambers 22 INVENTOK.

United States Patent.

3,058,735 TAPPING ROD WITH LIME COATING Caswell G. Chambers, Maryville, Tenn., assiguor of percent to William H. Shields, Maryville, Tenn. Filed Jan. 28, 1960, Ser. No. 5,205 2 Claims. (Cl. 266-42) This invention relates to a plug or tapping rod for a furnace.

An object of the invention is to provide a tapping rod for a furnace which possesses the advantage of facility in which the rod may be removed and having the further advantage of less likelihood of damage in that other types of rods freeze to the casting.

Another advantage in using a tapping rod in accordance with the invention is that there is less loss of metal from the furnace upon removal of the rod. Further, the use of the rod is clean in that no foreign materials are entered into the metal through the drain and there is no likelihood of injury to a workman such as results from the use of ordinary tapping rods because of the contact in other types of hot metal and moisture on the insulation ordinarily used. In other words, the procedure in accordance with the invention uses a dry or essentially dry tapping rod.

A further object of the invention is to provide a tapping rod which has a specially configured head and which is used with mortar lime on the surface thereof whereby the mortar lime is dry on the tapping rod when inserted in the furnace to eliminate the dangers of moisture on tapping rods or on the insulation of tapping rods. It has been found that mortar lime provides an excellent insulation and prevents bonding of the tapping rod head with the hot metal of the casting so that all that is required to remove the tapping rod is to strike it lightly and it breaks loose and removes very easily.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings formed a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a perspective view of a tapping rod in accordance with the invention.

FIGURE 2 is a horizontal sectional view showing the tapping rod being used in a typical situation.

FIGURE 3 is a sectional view taken on the line 3--3 of FIGURE 2.

In the accompanying drawings typical tapping rod is illustrated, and it is made of one piece forged metal. The rod has a shaft 12 with an eye 14 at the outer end of the shaft merely for convenience of use. The opposite end of the shaft is equipped with a head 16 of special shape. The extremity of head 16 is in the form of a cone, while the innermost part 18 of head 16 is in the form of a truncated cone joined to the base portion of the extremity 17 by means of an outwardly sloping wall 20.

Although the tapping rod 10 may be used singly, it is preferred that the tapping rod be used in pairs as shown in FIGURE 2.

Furnace 22 is shown in FIGURES 2 and 3 and has a tapping block or casting 24 disposed in an aperture 26' of the furnace, the aperture registering with the holding hearth 28 of the furnace. The furnace and tapping block are conventional and as such the tapping block has drains 32 and 34 therein to receive tapping rods 10.

In use, head 16 of typical tapping rod (FIGURE 3) is inserted into drain 32 until the point is two-thirds into the tapping block and in the hot metal. At this point the truncated conical part 18 of head 16 fits tightly against the outer edge of drain 32 with a portion of it extending inside of the casting. It is specifically pointed out that portion or part 18 of head 16 fits approximately twothirds of the way into the drain 32 i.e. about one-third measured along the length of part 18 is on the exterior of tapping block 24, and two-thirds of part 18 is on the interior of the tapping block 24.

The point of head part 17 conducts the heat into the tapping rod causing it to expand. This leads to a very important feature of the invention.

Before the tapping rod is inserted in the tapping block 24, head 16 is submersed or otherwise provided with a coating of mortar lime mixed with water. The mortar lime may be allowed to dry before inserting head 16 into the tapping block 24. Alternatively, since the mortar lime carries such a small amount of liquid, it may be inserted while it is still green. The function of the mortar lime is to insulate the head 16 from the metal in the holding hearth 28 and to prevent the head 16 from adhering to the metal. The prevention of adherence has been found to be so successful that the only thing required to remove the tapping rod is to strike it very lightly and it breaks loose. Because of the dry lime, the rod 10 may be reused immediately.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A tapping rod for a metallurgical furnace which has a tapping block provided with a drain said tapping rod comprising a shaft having a metallic head at one end, said head including a truncated conical part whose smaller diameter is smaller than the diameter of said drain and whose larger diameter is larger than the diameter of said drain so that upon insertion of said head into the drain a portion of the head remains on the exterior of the block and a portion of the head enters the tapping block drain, a coating of mortar lime on the truncated conical part of said head to prevent adherence of the hot metal to said head and to prevent the head from binding within said drain, said lime being free of lubricants and combustible materials whereby the plug will not be forced out of the drain by pressure of molten metal in the furnace.

2. A tapping rod for a metallurgical furnace containing molten metal and having a tapping block provided with a drain, said tapping rod comprising a metallic head at one end having a tapered part for engaging a sealing surface in said drain, said head having a portion adapted to extend exterior of said surface, and a coating of lime on said tapered part to insulate same and prevent its ad- 3 4 herence to said tapping block, said lime being free of 1,154,281 Bates Sept. 21, 1915 lubricants and combustible materials whereby the plug 1,277,899 Freeman Sept. 3, 1918 will not be forced out of the drain by the pressure of the FOREIGN PATENTS molten metal in the furnace.

5 43,353 Norway Nov. 8, 1926 References Cited in the file of this patent OTHER REFERENCES UNITED STATES PATENTS The Making, Shaping and Treating of Steel, 7th edi- 223,565 Webb Jan, 13, 1880 tion, pages 684 and 688, 1957- 295,661 Moller J 25, 1384 1 Pomp: The Manufacture and Properties of Steel Wire,

pp. 43 and 170, 1954. 

2. A TAPPING ROD FOR A METALLURGICAL FURNACE CONTAIN ING MOLTEN METAL AND HAVING A TAPPING BLOCK PROVIDED WITH A DRAIN, SAID TAPPING ROD COMPRISING A METALLIC HEAD AT ONE END HAVING A TAPERED PART FOR ENGAGING A SEALING SURFACE IN SAID DRAIN, SAID HEAD HAVING A PORTION ADAPTED TO EXTEND EXTERIOR OF SAID SURFACE, AND A COATING OF LINE ON SAID TAPERED PART TO INSULATE SAME AND PREVENT ITS AD- 